JPH0741321B2 - Method and device for manufacturing bent double pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The disclosed technology belongs to the field of manufacturing technology of a bent double pipe to be installed in the middle of piping of a double pipe laid in various plants or factories.

<Summary of Summary> Therefore, the invention of this application is a curved double pipe including an inner pipe made of stainless steel or the like having a predetermined curvature and an outer pipe made of carbon steel or the like, and is a straight double pipe or the like. A method for manufacturing a curved double pipe, in which the inner pipe and the outer pipe of the curved double pipe to be connected are connected via a thermal action,
And an invention relating to the apparatus, in particular, after an inner tube and an outer tube having a predetermined curvature are relatively layered to form a bending element tube, an annular heating device such as a high-frequency induction device for the outer tube and water supply before and after the heating annular device. An annular cooling device such as a shower ring with water is integrally set, and the annular heating device and the annular cooling device are relatively moved along the axial direction of the bending element tube, or swung in the circumferential direction, and the bending element tube Is an invention relating to a method and an apparatus for manufacturing a bent double pipe by ring thermal contraction such that the above is relatively moved.

<Prior Art> As is well known, pipes are widely used in all industries, and are used not only for fluid transport, which is a source of recent years, but also for structural members such as beam materials, and also for cable wiring. It is becoming more common in information transmission means such as protection tubes and mail air shooters that are surrounded by etc., and due to the diversification of its applications, there are strict requirements to surely meet various conditions during operation. It is getting done.

Therefore, the operating conditions of these kinds of pipes are severe,
Moreover, it is extremely difficult and difficult to create competing conditions with one material in the current material science, so it is necessary to deal with these problems in the double tube based on the double tube. For its creation,
For example, various double tubes have been developed and put into practical use by the clad method, the hydraulic tube expansion method, and the thermal tube expansion method as shown in many inventions of the applicant of the present invention.

Thus, pipes such as pipelines that are laid across a vast mountain or deep sea floor are generally long straight pipes, but in many plants such as factories In many cases, there are many pipe laying forms that bend due to the laying in narrow spaces, and further, due to the laying conditions such as the connection with other equipment, the pipes are not only simple long and short straight pipes, but also those A widely used mode is to connect and connect a bent pipe such as a so-called elbow pipe or a bent pipe between them.

Therefore, as described above, the straight pipe portion of the pipe has been widely used due to the operating conditions, and therefore the bent double pipe is naturally required for the bent pipe portion. Will be.

<Problems to be solved by the invention> However, the curved double pipe is different from the straight double pipe, and the double pipe technology that has been developed and adopted for the straight pipe has two types of bends due to its shape and other conditions. Heavy pipes have the disadvantage that they cannot be used directly, and as a result, curved double pipes have a high potential demand, but it is difficult to maintain a stable supply system of good quality. There are some disadvantages, and there is also the disadvantage that it results in higher costs.

However, although there is a technique disclosed in the invention of the applicant's earlier application, Japanese Patent Laid-Open No. 62-61773, there is a neck in which the thermal behavior of the pipe in the circumferential direction is insufficiently controlled. .

<Object of the Invention> The object of the invention of this application is to solve the problems of the bent double pipe based on the above-mentioned prior art, and the thermal management is easy, and the manufacturing can be performed at a relatively low cost and easily. A stable supply can be achieved in response to an increasing demand, and the control and management during manufacturing are easy, and the workability at the time of installation is good, and moreover, it can handle severe operating conditions like the straight pipe part. It is intended to provide an excellent method and apparatus for manufacturing a bent double pipe, which is advantageous in the field of application of piping technology in various industries.

<Means and Actions for Solving the Problem> In order to solve the above-mentioned problems, the structure of the invention of the present application, which is based on the above-mentioned object, is a double pipe pipe laid in a plant or the like. In the curved double pipe in which a double pipe of a predetermined design can be installed by interposing the double pipe of the straight pipe portion, for example, carbon steel is used for the inner pipe made of stainless steel or the like having a predetermined curvature. An outer tube made of, for example, a product is relatively laminated to form a bending element tube, and an annular heating device such as a high-frequency induction heating device is set to the outer tube of the bending element tube, and before and after that an annular cooling such as a showering device with tap water. The device is also integrally set, and the annular heating device and the annular cooling device are caused to pivot with respect to the bending element tube in the circumferential direction thereof and at the same time relatively moved in the axial direction thereof through the moving device, or vice versa. The bent tube is used as an annular heating and cooling device. To prevent the expansion of the outer tube due to annular heating and restrain it by making it move relative to each other, and to yield by the bending moment of the press to tightly fasten the outer tube to the inner tube and obtain a reliable tightly bent double tube. It is a technical measure that makes it possible.

<Example> Next, an example of the invention of this application will be described with reference to the drawings.

In the embodiment of the basic principle mode shown in FIGS. 5 to 8, as shown in FIG. 5, the outer tube 1 made of carbon steel or the like and the inner tube 2 made of stainless steel or the like are used as the raw tube 3 which is relatively laminated, An annular heating device 4 such as a high frequency induction heating device is set at a predetermined portion of the outer tube 1, and an annular cooling device 5 or 5 such as a showering device with tap water is set before and after the annular heating device 4 to integrate the both. As shown in the figure, for example, the element tube 3 in the arrow direction,
That is, it moves in the axial direction relative to the annular heating device 4 and the annular cooling devices 5 and 5.

By doing so, in the case of the outer tube 1 in the case of a short tube having an end, it tries to expand by annular heating, but both ends are restrained continuously, and moreover, by the annular cooling device 5, 5. Because of the restraint, the expansion diameter is prevented, the plastic deformation is gradually caused, and the product finally yields and, as shown in FIG. 8, the holding bending moment F acts on the outer pipe 1 to make close contact with the inner pipe 2. By repeating the relative movement in the directions, the outer tube 1 becomes the inner tube 2
On the other hand, by tightly fastening, as shown in FIG. 7, a tightly connected double tube 6 can be obtained.

It should be noted that, contrary to the above-described aspect, the annular heating device 4 and the annular cooling device 5 are
Needless to say, it is also possible to move and in the axial direction with respect to the bending element tube 3.

Such a so-called ring thermal contraction method is disclosed in detail in the applicant's prior invention, has already entered a practical stage, and can be easily implemented by those skilled in the art.

An example in which the basic technique for producing a double tube by the ring heat reduction method is applied to a curved double tube will now be described with reference to FIGS. In the embodiment of displacement on the tube side shown in the figure, a stainless steel inner tube 2 having a predetermined curvature and a carbon steel outer tube 1 having the same curvature are relatively laminated to form a bending element tube 3 ', which is clamped at one end thereof. An arm 9 as a moving device is connected to the bracket 8 and linked to a rotary shaft 10. The rotary shaft 10 is connected to a servomotor 12 through a gear mechanism 11 such as a worm, and the bending element tube 3'is rotated. The ring-shaped bracket 7 which is rotatably movable along the shaft 10 and which is mounted on a predetermined portion of the bending element tube 3'is provided with a ring-shaped heating device 4 of the high-frequency induction heating device as in the above-described basic embodiment. And an annular cooling device 5 such as a shower ring device with tap water before and after the A predetermined tap water source 18 is provided by a pump device 17 through a swivel joint 16 provided on a ring-shaped bracket 7 integrally connected to the racket.
And the ring-shaped bracket 7
Is provided with a ring gear 13 and is connected to a servomotor 15 as a circumferential turning device via a gear type speed reducer 14, that is, the ring gear 13, that is, the bending element tubes of the annular heating device 4 and the annular cooling devices 5 and 5. The bracket 3 and the bending element pipe 3'are made to be reciprocally movable relative to each other in the axial direction of the bending element tube 3 '.

In the above structure, by rotating the servomotor 12 and the servomotor 15 in steps, the bending element tube 3'reciprocates and turns at a predetermined speed via the rotating ring-shaped bracket 7.

For the outer tube 1 of the bent element tube 3 ', the annular heating device 4 and the annular cooling devices 5, 5 are provided as in the embodiment of the above-described principle mode.
The outer tube 1 is yielded and closely adheres to the inner tube 2 due to the ring heat reduction effect of (1), and thus a tightly bent double tube is obtained.

The embodiment shown in FIGS. 3 and 4 is an embodiment in which a slip ring 23 is mounted on the bending element tube 3 ', and there is substantially no difference in the action and effect from the above-mentioned embodiments.

In the above-mentioned embodiments, the curved double pipe 3'is configured to be pivotally moved relative to the ring-shaped bracket 7, which is shown in FIGS. On the contrary, in the embodiment, the annular heating device 4 and the annular cooling device 5 of the ring-shaped brackets 7'and 7'are provided for the curved double pipe 3'of which the position and orientation are fixed.
5 is an integrally connected body and is made to pivot along the axial direction of the bending element tube 3 '. In this embodiment, the arms 9', 9'of the ring-shaped brackets 7 ', 7'.
This is a mode in which dogs 22, 22 are provided on the limit switch 21 so as to be able to come into contact with and separate from the limit switch 21 so that the rotation speed in the swing motion can be freely switched, and the swing operation is automatically switched via the control device 19. This is a mode in which there is substantially no difference from the above-described embodiment, and a more reliable tightly bent double pipe can be obtained.

Further, in this embodiment, it is possible to rotate the annular heating device 4 and the annular cooling device 5 around their central axes.

Needless to say, the embodiment of the invention of this application is not limited to the above-mentioned embodiments. For example, even if an intermediate pipe is interposed between the inner pipe and the outer pipe, a substantially more reliable tight-bending is achieved. Various modes such as a double tube can be adopted.

<Effects of the Invention> As described above, according to the invention of this application, when the pipe laid in a plant such as a plant is a double pipe, it is connected to a double pipe of a straight pipe portion to form a pipe according to a predetermined design. When laying, the bent double pipe can be easily designed by a person skilled in the art because the developed ring thermal contraction method can be applied in the invention of the applicant's prior invention. Like the double pipe of the straight pipe, the double pipe can be stably supplied with high accuracy, and further, the cost can be reduced.

Thus, in the elementary pipe stage, after the inner pipe and the outer pipe are layered relative to each other, annular heating is applied to the outer pipe and annular cooling is applied before and after the outer pipe, whereby the expansion diameter of the outer pipe is restricted and the holding bending moment is reduced. An excellent effect can be obtained in which a double tube is formed by tightly bending the outer tube by applying it to the inner tube and bringing them into close contact with the inner tube.

Therefore, an excellent effect that a reliable double tube can be obtained can be obtained even though it is a bent double tube.

Thus, the curved element pipes of the inner tube and the outer tube, which are layered relative to each other with respect to the annular heating device and the annular cooling device, are swung relative to each other and moved in the axial direction, so that the entire area of the curved element tube is externally moved. The pipe can be tightly connected to the inner pipe, and the excellent effect that a surely bent double pipe as designed can be obtained.

Then, the bending element tube side is relatively rotated with respect to the annular heating device and the annular cooling device, and is moved in the axial direction through the moving device, so that the annular cooling device does not need a seal and is attached to the side. It is easy to perform maintenance and inspection, and it is also cost effective.

On the contrary, by rotating the annular heating device and the annular cooling device relatively in the axial direction with respect to the bending element pipe, power supply to the bending element tube and a large moving device are not required, and a flip ring or There is a merit that the Swivel Joint can be made smaller.

Then, by rotating the annular heating device in the circumferential direction of the tube, an excellent effect that the heating applying action is uniformly performed is exhibited.

[Brief description of drawings]

1 to 4 are explanatory views of an embodiment of the invention of this application,
1 is an overall schematic side view of one embodiment, FIG. 2 is a partially enlarged side view of the same, FIG. 3 is a cross-sectional view of another embodiment corresponding to FIG. 2, and FIG. 4 is another embodiment. Overall schematic side view, FIGS. 5 to 8 are explanatory views of the basic embodiment, FIG. 5 is a partial sectional side view of a bend, and FIG. 6 is a partial sectional side view of annular heating and annular cooling application, FIG. 7 is a partial cross-sectional side view of the double pipe, and FIG. 8 is a schematic perspective view of applying a presser bending moment. A, A '... Double pipe manufacturing device, 2 ... Inner pipe, 1 ... Outer pipe, 3' ... Bent element pipe, 4 ... Annular heating device, 5 ... Annular cooling device, 9, 9 ' ...... Mobile device

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kiyoshi Yamashita 3-1-1 Higashikawasaki-cho, Chuo-ku, Kobe-shi, Hyogo Kawasaki Heavy Industries, Ltd. Kobe factory (56) Reference Japanese Patent Publication 5-76384 (JP, B2) )

Claims (2)

[Claims] 1. A method for producing a curved double tube in which a curved element tube composed of an inner tube and an outer tube is tightly bonded by a thermal action, wherein the inner tube and the outer tube are relatively laminated to form a curved element tube, and then the bent element is outside. The annular heating of the tube and at least one of the annular cooling before and after the annular heating are relatively moved along the axial direction of the curved element tube, and the annular heating and the annular cooling are relatively the same to the curved element tube. A method for manufacturing a bent double pipe, characterized in that it is applied while being rotated in a direction. 2. A curved double tube manufacturing apparatus in which a curved element tube composed of an inner tube and an outer tube is tightly bonded together by thermal action, and a curved element tube in which the inner tube and the outer tube of the curved tube are relatively laminated. Bending double pipe manufacturing characterized by comprising an annular heating device provided on the outside of the outer pipe, an annular cooling device relative to the front and rear of the outer heating device, and a relative axial moving device equipped with these circumferential turning devices. apparatus.